Circuit breaker, arcing chamber housing for a circuit breaker and housing module for an arcing chamber housing

ABSTRACT

A arcing chamber housing is disclosed for a circuit breaker with a double turning contact breaker. The arcing chamber housing (1) is composed of two housing modules (2, 3) and an extinguishing chamber (19) is arranged in the area of the fixed contact pieces (6, 7) to extinguish the arcs which are formed between the contact pieces of the double turning contact breaker. In order to obtain a arcing chamber housing (1) which is easy and economical to produce, with extinguishing chambers (19) which have a reproducible extinguishing behavior once the arcing chamber is assembled, the two housing modules (2, 3) are substantially L-shaped parts whose inner marginal surfaces (4, 5) face each other. The first parts (17, 18) of the housing, which correspond to the first branches of the L-shaped housing modules (2,3), are designed as extinguishing chambers (19). Also disclosed are the housing modules (2, 3) used to produce such a arcing chamber housing.

FIELD OF THE PRESENT INVENTION

The invention relates to an arcing chamber housing for a circuit breakerhaving a rotary double-break interrupter. The present invention relatesfurthermore to housing modules for manufacturing an arcing chamberhousing of this kind.

BACKGROUND OF THE INVENTION

Arcing chamber housings which are designed for circuit breakers and areable to be assembled from two separate housing modules for each powersupply phase are disclosed, for example in European Patent No. B 1-542636. These housings can be assembled simply and quickly. In addition, itis merely the relatively small arcing chamber housing that needs to bemade of an arc-resistant material. On the other hand, the housing whichis placed over the arcing chamber housings that correspond in number tothe number of phases, can be made of a less expensive material. Thedisclosed housing modules are essentially constituted of twosaucer-shaped housing parts, symmetrically disposed with respect to themedian plane in the longitudinal direction of the arcing chamberhousing. To assemble the arcing chamber, initially the contact members,arc splitters, etc. are arranged in one of the two saucer-shaped housingmodules, and the second housing module, as the case may be, is thenplaced upon the first housing module and joined, e.g., riveted thereto.The disadvantage of the known arcing chamber housings is, inter alia,that the extinction chambers of arcing chamber housings of this kind arefirst formed when the two housing modules are joined. For that reason,it is not possible, as a rule, to perform a complete test for correctfunctioning of the extinction chambers prior to their assembly. Toeliminate sources of error, in particular in the arcing chambers, it isoften necessary to disassemble the entire arcing chamber when knownarcing chamber housings are used.

SUMMARY OF THE INVENTION

An object of the invention is to indicate an arcing chamber housingwhich is capable of being assembled from two housing modules and whichhas the advantages of known housings of this kind, is simple andinexpensive, and in which the extinction chambers, following assembly ofthe arcing chambers, have reproducible arc-quenching performancecharacteristics. In addition, the intention is to provide housingmodules capable of being used for manufacturing arcing chamber housingsof this kind.

The present invention provides an arcing chamber housing in which thearcing chamber housing is to be assembled from two essentially L-shapedhousing modules, whose first housing part corresponding to a first limbis designed as an extinction chamber.

It is preferable that the two interconnected housing modules have anidentical construction, so that there is no need for them to bemanufactured and stockpiled separately.

The present invention also provides a housing module in which a firsthousing part that constitutes the first limb of the L-shaped housingmodule is designed as extinction chamber (19). One of the stationarycontact members, as well as the arm of the rotatable contact memberassigned to the stationary contact member in question are arrangedinside the extinction chamber, and the second housing part of thehousing module that constitutes the second limb is designed as a bearingblock for a shaft that actuates the rotatable contact member.

In this context, the side walls of the second housing part forming thesecond bearing block are expediently provided with semicircularopenings.

A significant advantage of the arcing chamber housings of the presentinvention is that, in each housing module, prior to assembling thearcing chamber housing, the appropriate arcing chamber can be completelypreassembled, together with its arc splitters and, if indicated, testedfor its functioning.

The same applies to the two stationary contact members and the rotatablecontact member. In this context, depending on the design of the L-shapedhousing module and of the contact members, the two stationary contactmembers can each be permanently preassembled in one housing module, orboth contact members together in only one housing module. In the secondcase then, assembling the arcing chamber housing merely requiressecuring the second housing module, as the case may be, together withthe corresponding arcing chamber, to the first housing module having theotherwise completely installed rotary double-break interrupter.

In one advantageous specific embodiment, the housing modules aredesigned at the same time to be supporting structures for therail-shaped conductors arranged between the stationary contact member inquestion and the connecting terminal in question.

For this, provision is made at the edges, on one or both outer sides ofthe first housing part, for depressions, into which are insertablecorresponding rail-shaped conductors having a loop form, in particularhaving connecting crosspieces at the extremities. In another specificembodiment of the present invention, a depression is also provided onthe outer side of the second housing part as well, in the edge areafacing away from the first housing part. A partial section of therail-shaped conductor arranged between the stationary contact member inquestion and the corresponding connecting terminal can also be insertedin this depression.

It is practical for the housing module to be made of a molded plasticarticle.

BRIEF DESCRIPTION OF THE DRAWINGS

The following exemplary embodiments reveal further details andadvantages of the invention, as elucidated on the basis of the Figures,which show:

FIG. 1 illustrates the side view of a first exemplary embodiment of anarcing chamber housing of the present invention, including contactmembers shown with dotted lines;

FIG. 2 illustrates a perspective view of one of the two housing modulesof FIG. 1; and

FIG. 3 illustrates a perspective view of a second exemplary embodimentof an arcing chamber housing of the present invention prior toassembling the two housing modules, both the stationary contact membersas well as the rotatable contact member being completely preassembled onone housing module.

DETAILED DESCRIPTION

In FIG. 1, 1 denotes an arcing chamber housing, which is composed of twosame, L-shaped housing modules 2 and 3, whose inner boundary surfaces 4,5 face one another. The housing modules are made, for example, from asuitable molded plastic article.

Located in arcing chamber housing 1 is a generally known rotarydouble-break interrupter, which essentially includes two stationarycontact members 6, 7 and a contact member 9 that is rotatable about ashaft 8 and that jumpers the two stationary contact members. Stationarycontact members 6, 7 are each connected via rail-shaped conductors 10,11 to corresponding connecting terminals 12, 13. A shaft 14 enables therotatable contact member 9 to swivel in the direction of arrow 15. Todrive shaft 14, or to couple shaft 14 to corresponding rotarydouble-break interrupters, connected in parallel, for additional phases,shaft 14 is led through side wall 16 of arcing chamber housing 1. Firsthousing part 17 or 18 corresponding to the first limb, shown vertically,of the L-shaped housing module 2 or 3 in question, contains in each casean arcing chamber 19 (FIG. 2), with stationary contact member 6 or 7, aswell as arm 20 or 21 of rotatable contact member 9 associated with thiscontact member being arranged within this arcing chamber 19. Secondhousing part 22 or 23 of housing module 2 or 3 in question forming thesecond limb, shown horizontally, is designed as a bearing block forshaft 14 of rotatable contact member 9, side walls 24, 26 or 25 ofsecond housing part 22 or 23 forming the bearing block havingsemicircular openings 27, 29 or 28, which surround shaft 14.

Assembling the entire arcing chamber housing 1 is a simple operation:the arc splitters (not shown) and stationary contact members 6, 7 havingrail-shaped conductors 10, 11 are inserted and installed in the twofinished housing modules 2, 3; and, if indicated, the functioning ofarcing chambers 19 is tested. In addition, in one of the two housingparts 22, 23, rotatable contact member 9 is inserted and, if indicated,secured. The two housing modules 2, 3, including the preassembledswitching contact parts are then joined together, for example,screw-coupled, riveted, latched or welded together.

The present invention is, of course, not limited to the exemplaryembodiment described above. It is not necessary that the two housingmodules have an exact L-shaped form. It is, rather, customary for theouter contour of the housing modules, in particular, to deviate from theL-shape, to enable the arcing chamber housing to be inserted into thecorresponding housing placed above it.

Moreover, the housing does not have to be designed to accommodate therail-shaped conductors in the arcing chamber as well. It has proven tobe advantageous, for example, when working with relatively longconductors, to use the particular intended housing module as asupporting structure for the conductors that are able to be mounted onthe exterior of the housing module in question. An exemplary embodimentof this kind is shown in FIG. 3:

In this instance, arcing chamber housing, denoted by 30, is made up, inturn, of two identical, essentially L-shaped housing modules 31, 32.Each housing module 31 or 32 has, respectively, a first housing part 33or 34, and a second housing part 35 or 36. Of the two stationary contactmembers 37, only the contact member on the right is visible in FIG. 3,the other contact member is arranged inside first housing part 33. Thedesign of housing modules 31, 32 is such that both the two stationarycontact members 37, as well as rotatable contact member 38 are able tobe optionally preassembled on one of the two housing modules 31, 32 tobe joined together. The other housing module in each case still containsthen merely an extinction chamber, in some instances with arc splitters.

In the depicted exemplary embodiment, rail-shaped conductors 41, 42connecting stationary contact members 37 and connecting terminals 39, 40are each conceived as U-shaped or L-shaped double loops, to be arrangedin edge-side depressions 45, 46 or 43, 44 on outer sides 47, 48 or 49,50 of first or second housing part 33, 34 or 35, 36. In this context,the loop ends are interconnected via conductive connecting crosspieces51, 52.

What is claimed is:
 1. An arcing chamber housing for a circuit breakercomprising:a first housing module, the first housing module beingessentially L-shaped and having a first housing limb; and a secondhousing module, the second housing module being essentially L-shaped andhaving a second housing limb and an inner edge surface, the inner edgesurface facing the first housing module, the first and second housingmodules for housing a rotary double-break interrupter of the circuitbreaker, the rotary double-break interrupter including a first and asecond stationary contact member connected via rail-shaped conductors torespective first and second connecting terminals, the rotarydouble-break interrupter including a two-arm rotatable contact memberrotatable about a shaft for connecting in a closed position the firstand second stationary contact members, the first and second stationarycontact members in response to an overload situation for swivelling therotatable contact member into an open position; the first and secondhousing limbs each forming an arc extinction chamber for the rotarydouble-break interrupter in an area of the first and second stationarycontact members.
 2. The arcing chamber housing as recited in claim 1wherein the first and second housing modules are identical.
 3. AnL-shaped housing module for an arcing chamber housing comprising:a firsthousing part forming a first limb, the first limb including an arcextinction chamber for a rotary double-break interrupter, the first limbfor housing a stationary contact member and an arm of a rotatablecontact member of the rotary double-break interrupter; and a secondhousing part forming a second limb, the second limb including a bearingblock for a shaft for actuating the rotatable contact member.
 4. Thehousing module as recited in claim 3 wherein the second housing part hasside walls having semicircular openings.
 5. The housing module asrecited in claim 3 wherein the first housing part has at least one outerside having an edge-side depression for supporting a rail-shapedconductor having a loop form between the stationary contact member and acorresponding connecting terminal.
 6. The housing module as recited inclaim 5 wherein the outer side is capable of supporting a secondrail-shaped conductor having a loop form, the second rail-shapedconductor for interconnection via a connecting crosspiece to therail-shaped conductor.
 7. The housing module as recited in claim 5wherein the second housing part has at least one second outer side witha second edge-side area facing away from the first housing part andhaving a second depression for at least one partial section of therail-shaped conductor.
 8. The housing module as recited in claim 5wherein the housing module is made of a molded plastic.
 9. A circuitbreaker comprising:a rotary double-break interrupter including a firstand a second stationary contact member and a two-arm rotatable contactmember rotatable about a shaft for connecting in a closed position thefirst and second stationary contact members, the first and secondstationary contact members in response to an overload situation forswivelling the rotatable contact member into an open position; a firsthousing module, the first housing module being essentially L-shaped andhaving a first housing limb; and a second housing module, the secondhousing module being essentially L-shaped and having a second housinglimb and an inner edge surface, the inner edge surface facing the firsthousing module, the first and second housing modules for housing therotary double-break interrupter, the first and second housing limbs eachforming an arc extinction chamber in an area of the first and secondstationary contact members.